A new study led by researchers at McMaster University suggests that living in a deprived urban neighborhood and experiencing depression symptoms may cause faster aging at the cellular level.
The findings, published in The Journals of Gerontology, indicate that material and social inequities in urban environments, along with depression, are independently associated with premature biological aging, even when accounting for individual health and behavioral factors.
The research team, led by Professor Parminder Raina from McMaster University, included investigators from the Netherlands, Norway, and Switzerland. The study utilized epigenetic clocks, which are DNA methylation-based estimators, to assess aging at the cellular level and calculate the difference between chronological age and biological age.
According to Divya Joshi, the study’s first author and a research associate at McMaster, the results revealed that living in deprived neighborhoods and experiencing depressive symptoms were linked to accelerated biological aging as estimated by the DNAm GrimAge clock. These findings contribute to the growing body of evidence suggesting that residing in urban areas with higher levels of neighborhood deprivation and experiencing depression symptoms are associated with premature biological aging.
Depressive symptoms were measured using a standardized depression scale consisting of ten items. The researchers discovered that an increase in the depressive symptom score corresponded to a one-month acceleration in the risk of death. They theorized that emotional distress caused by depression might lead to increased biological wear and tear and dysregulation of physiological systems, resulting in premature aging.
The researchers evaluated neighborhood deprivation by employing two indices developed by the Canadian Urban Environmental Health Research Consortium (CANUE), based on the 2011 census. Social deprivation measured the presence of fewer social resources within the family and community, while material deprivation reflected the inability to access goods and conveniences of modern life, such as adequate housing, nutritious food, transportation, high-speed internet, or recreational facilities in the neighborhood.
The study revealed that individuals exposed to greater neighborhood deprivation faced an increased risk of death by almost one year compared to those in lower deprivation areas. However, the study did not find evidence that neighborhood deprivation amplified the effect of depressive symptoms on epigenetic age acceleration.
Joshi stated, “Our results showed that the effect of neighborhood deprivation on epigenetic age acceleration was similar regardless of depression symptoms, suggesting that depression influences epigenetic age acceleration through mechanisms unrelated to neighborhood deprivation.”
The research utilized epigenetic data from 1,445 participants enrolled in the Canadian Longitudinal Study on Aging (CLSA), a long-term research platform following over 50,000 participants aged 45 to 85 at recruitment. Raina, the senior author of the study and the lead principal investigator of the CLSA, emphasized the importance of longitudinal studies like the CLSA to confirm the associations found in this research. Such studies can determine whether epigenetic changes are stable or reversible over time and shed light on the mechanisms contributing to accelerated epigenetic aging.
The Canadian Longitudinal Study on Aging receives support from the Government of Canada through the Canadian Institutes of Health Research and the Canada Foundation for Innovation. Additionally, this study received additional support from the European Union Horizon 2020 Programme.
